xref: /openbmc/linux/drivers/rtc/rtc-pcf50633.c (revision be709d48)
1 /* NXP PCF50633 RTC Driver
2  *
3  * (C) 2006-2008 by Openmoko, Inc.
4  * Author: Balaji Rao <balajirrao@openmoko.org>
5  * All rights reserved.
6  *
7  * Broken down from monstrous PCF50633 driver mainly by
8  * Harald Welte, Andy Green and Werner Almesberger
9  *
10  *  This program is free software; you can redistribute  it and/or modify it
11  *  under  the terms of  the GNU General  Public License as published by the
12  *  Free Software Foundation;  either version 2 of the  License, or (at your
13  *  option) any later version.
14  *
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/device.h>
21 #include <linux/slab.h>
22 #include <linux/platform_device.h>
23 #include <linux/rtc.h>
24 #include <linux/bcd.h>
25 #include <linux/err.h>
26 
27 #include <linux/mfd/pcf50633/core.h>
28 
29 #define PCF50633_REG_RTCSC	0x59 /* Second */
30 #define PCF50633_REG_RTCMN	0x5a /* Minute */
31 #define PCF50633_REG_RTCHR	0x5b /* Hour */
32 #define PCF50633_REG_RTCWD	0x5c /* Weekday */
33 #define PCF50633_REG_RTCDT	0x5d /* Day */
34 #define PCF50633_REG_RTCMT	0x5e /* Month */
35 #define PCF50633_REG_RTCYR	0x5f /* Year */
36 #define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
37 #define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
38 #define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
39 #define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
40 #define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
41 #define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
42 #define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */
43 
44 enum pcf50633_time_indexes {
45 	PCF50633_TI_SEC,
46 	PCF50633_TI_MIN,
47 	PCF50633_TI_HOUR,
48 	PCF50633_TI_WKDAY,
49 	PCF50633_TI_DAY,
50 	PCF50633_TI_MONTH,
51 	PCF50633_TI_YEAR,
52 	PCF50633_TI_EXTENT /* always last */
53 };
54 
55 struct pcf50633_time {
56 	u_int8_t time[PCF50633_TI_EXTENT];
57 };
58 
59 struct pcf50633_rtc {
60 	int alarm_enabled;
61 	int alarm_pending;
62 
63 	struct pcf50633 *pcf;
64 	struct rtc_device *rtc_dev;
65 };
66 
67 static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
68 {
69 	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
70 	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
71 	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
72 	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
73 	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
74 	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
75 	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
76 }
77 
78 static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
79 {
80 	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
81 	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
82 	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
83 	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
84 	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
85 	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
86 	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
87 }
88 
89 static int
90 pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
91 {
92 	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
93 	int err;
94 
95 	if (enabled)
96 		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
97 	else
98 		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
99 
100 	if (err < 0)
101 		return err;
102 
103 	rtc->alarm_enabled = enabled;
104 
105 	return 0;
106 }
107 
108 static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
109 {
110 	struct pcf50633_rtc *rtc;
111 	struct pcf50633_time pcf_tm;
112 	int ret;
113 
114 	rtc = dev_get_drvdata(dev);
115 
116 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
117 					    PCF50633_TI_EXTENT,
118 					    &pcf_tm.time[0]);
119 	if (ret != PCF50633_TI_EXTENT) {
120 		dev_err(dev, "Failed to read time\n");
121 		return -EIO;
122 	}
123 
124 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
125 		pcf_tm.time[PCF50633_TI_DAY],
126 		pcf_tm.time[PCF50633_TI_MONTH],
127 		pcf_tm.time[PCF50633_TI_YEAR],
128 		pcf_tm.time[PCF50633_TI_HOUR],
129 		pcf_tm.time[PCF50633_TI_MIN],
130 		pcf_tm.time[PCF50633_TI_SEC]);
131 
132 	pcf2rtc_time(tm, &pcf_tm);
133 
134 	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
135 
136 	return 0;
137 }
138 
139 static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
140 {
141 	struct pcf50633_rtc *rtc;
142 	struct pcf50633_time pcf_tm;
143 	int alarm_masked, ret = 0;
144 
145 	rtc = dev_get_drvdata(dev);
146 
147 	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
148 
149 	rtc2pcf_time(&pcf_tm, tm);
150 
151 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
152 		pcf_tm.time[PCF50633_TI_DAY],
153 		pcf_tm.time[PCF50633_TI_MONTH],
154 		pcf_tm.time[PCF50633_TI_YEAR],
155 		pcf_tm.time[PCF50633_TI_HOUR],
156 		pcf_tm.time[PCF50633_TI_MIN],
157 		pcf_tm.time[PCF50633_TI_SEC]);
158 
159 
160 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
161 
162 	if (!alarm_masked)
163 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
164 
165 	/* Returns 0 on success */
166 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
167 					     PCF50633_TI_EXTENT,
168 					     &pcf_tm.time[0]);
169 
170 	if (!alarm_masked)
171 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
172 
173 	return ret;
174 }
175 
176 static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
177 {
178 	struct pcf50633_rtc *rtc;
179 	struct pcf50633_time pcf_tm;
180 	int ret = 0;
181 
182 	rtc = dev_get_drvdata(dev);
183 
184 	alrm->enabled = rtc->alarm_enabled;
185 	alrm->pending = rtc->alarm_pending;
186 
187 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
188 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
189 	if (ret != PCF50633_TI_EXTENT) {
190 		dev_err(dev, "Failed to read time\n");
191 		return -EIO;
192 	}
193 
194 	pcf2rtc_time(&alrm->time, &pcf_tm);
195 
196 	return rtc_valid_tm(&alrm->time);
197 }
198 
199 static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
200 {
201 	struct pcf50633_rtc *rtc;
202 	struct pcf50633_time pcf_tm;
203 	int alarm_masked, ret = 0;
204 
205 	rtc = dev_get_drvdata(dev);
206 
207 	rtc2pcf_time(&pcf_tm, &alrm->time);
208 
209 	/* do like mktime does and ignore tm_wday */
210 	pcf_tm.time[PCF50633_TI_WKDAY] = 7;
211 
212 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
213 
214 	/* disable alarm interrupt */
215 	if (!alarm_masked)
216 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
217 
218 	/* Returns 0 on success */
219 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
220 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
221 	if (!alrm->enabled)
222 		rtc->alarm_pending = 0;
223 
224 	if (!alarm_masked || alrm->enabled)
225 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
226 	rtc->alarm_enabled = alrm->enabled;
227 
228 	return ret;
229 }
230 
231 static const struct rtc_class_ops pcf50633_rtc_ops = {
232 	.read_time		= pcf50633_rtc_read_time,
233 	.set_time		= pcf50633_rtc_set_time,
234 	.read_alarm		= pcf50633_rtc_read_alarm,
235 	.set_alarm		= pcf50633_rtc_set_alarm,
236 	.alarm_irq_enable	= pcf50633_rtc_alarm_irq_enable,
237 };
238 
239 static void pcf50633_rtc_irq(int irq, void *data)
240 {
241 	struct pcf50633_rtc *rtc = data;
242 
243 	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
244 	rtc->alarm_pending = 1;
245 }
246 
247 static int pcf50633_rtc_probe(struct platform_device *pdev)
248 {
249 	struct pcf50633_rtc *rtc;
250 
251 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
252 	if (!rtc)
253 		return -ENOMEM;
254 
255 	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
256 	platform_set_drvdata(pdev, rtc);
257 	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "pcf50633-rtc",
258 				&pcf50633_rtc_ops, THIS_MODULE);
259 
260 	if (IS_ERR(rtc->rtc_dev))
261 		return PTR_ERR(rtc->rtc_dev);
262 
263 	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
264 					pcf50633_rtc_irq, rtc);
265 	return 0;
266 }
267 
268 static int pcf50633_rtc_remove(struct platform_device *pdev)
269 {
270 	struct pcf50633_rtc *rtc;
271 
272 	rtc = platform_get_drvdata(pdev);
273 	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);
274 
275 	return 0;
276 }
277 
278 static struct platform_driver pcf50633_rtc_driver = {
279 	.driver = {
280 		.name = "pcf50633-rtc",
281 	},
282 	.probe = pcf50633_rtc_probe,
283 	.remove = pcf50633_rtc_remove,
284 };
285 
286 module_platform_driver(pcf50633_rtc_driver);
287 
288 MODULE_DESCRIPTION("PCF50633 RTC driver");
289 MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
290 MODULE_LICENSE("GPL");
291 
292